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Wierd issue when running with jest

See original GitHub issue

I know this is very little information, but I’ve encountered the following when executing some tests with Jest, which touches code that connects to MySQL using node-mysql2, but the code makes no queries.

Any ideas on what causes this issue? The code is fine, when executed directly.

PROJECT_FOLDER/node_modules/jest-runtime/build/index.js:439
    const wrapper = this._environment.runScript(script)[
                                                       ^

TypeError: Cannot read property 'Object.<anonymous>' of null
    at Runtime._execModule (PROJECT_FOLDER/node_modules/jest-runtime/build/index.js:439:56)
    at Runtime.requireModule (PROJECT_FOLDER/node_modules/jest-runtime/build/index.js:296:14)
    at Runtime.requireModuleOrMock (PROJECT_FOLDER/node_modules/jest-runtime/build/index.js:365:19)
    at Object.getCodec (PROJECT_FOLDER/node_modules/iconv-lite/lib/index.js:61:27)
    at Object.getDecoder (PROJECT_FOLDER/node_modules/iconv-lite/lib/index.js:118:23)
    at Object.<anonymous>.exports.decode (PROJECT_FOLDER/node_modules/mysql2/lib/parsers/string.js:19:23)
    at Packet.Object.<anonymous>.Packet.readNullTerminatedString (PROJECT_FOLDER/node_modules/mysql2/lib/packets/packet.js:371:23)
    at Function.Object.<anonymous>.Handshake.fromPacket (PROJECT_FOLDER/node_modules/mysql2/lib/packets/handshake.js:19:31)
    at ClientHandshake.Object.<anonymous>.ClientHandshake.handshakeInit (PROJECT_FOLDER/node_modules/mysql2/lib/commands/client_handshake.js:83:38)
    at ClientHandshake.Object.<anonymous>.Command.execute (PROJECT_FOLDER/node_modules/mysql2/lib/commands/command.js:39:20)

Issue Analytics

State:
Created 7 years ago
Reactions:11
Comments:11 (7 by maintainers)

Top GitHub Comments

20reactions

opatutcommented, Jul 6, 2017

I found a temporary workaround for now, add this to your setupTestFrameworkScriptFile:

// Hack to make iconv load the encodings module, otherwise jest crashes. Compare
// https://github.com/sidorares/node-mysql2/issues/489
require('mysql2/node_modules/iconv-lite').encodingExists('foo');

Might look a bit different depending on your setup 😉

4reactions

v1d3rm3commented, Dec 22, 2018

I found a temporary workaround for now, add this to your setupTestFrameworkScriptFile:
// Hack to make iconv load the encodings module, otherwise jest crashes. Compare
// https://github.com/sidorares/node-mysql2/issues/489
require('mysql2/node_modules/iconv-lite').encodingExists('foo');
Might look a bit different depending on your setup 😉

In typescript, just do:

// Hack to make iconv load the encodings module, otherwise jest crashes. Compare
// https://github.com/sidorares/node-mysql2/issues/489
import * as iconv from 'iconv-lite';
iconv.encodingExists('foo');

In my case, foo was cp1252